n. A synthetic thespian; a simulated character who "acts" in 3-D animations and games, such as Woody and Buzz Lightyear in Toy Story.
The synthespian, an artificially-created 'human' actor, is the Hollywood Screen Actors' Guild's nightmare. … The word — and, yes, it's an awful one — was coined by LA-based digital effects expert Jeff Kleiser when he created the industry's first virtual actor (or 'vactor') for his 1988 short film Nestor Sextone for President.
In 1988 Kleiser and Walczak produced a short satirical piece called 'Sextone for President,' which centered on a bid by a 'synthespian' named Nestor Sextone to become president of the Synthetic Actors Guild. The muscle-bound Sextone complains that live actors have been masquerading as synthetics and thus robbing them of jobs (a thinly veiled reference to 'Max Headroom').